MODERNIZATION OF RUSSIAN CLOSE-IN AIR DEFENSE SYSTEMS

Close-in air defense (AD) systems play special role among field
air defense weapons. Their primary task is to provide air defense of motorized and tank
units and subunits in maneuvering combat and on the march by delivering fire on the move.
Besides, practical close-in fighting requires that the systems be outfitted with effective
AD guns capable of engaging both air and ground targets. The most successful type of these
weapon systems is Russias famous Shilka self-propelled AD gun mount developed in the
early 1960s and designed to fight primarily tactical aircraft and helicopters. The advent
of tactical precision-guided weapons (PGW) called for the introduction of a missile
channel to fight aircraft and helicopters before they could fire PGW. As a consequence,
the renowned Tunguska AD gun-missile system was developed by the Tula Instrument Design
Bureau and built in the 1980s.

Shilka SP gun mount

The intense
development of air attack weapons has changed the approach to the modernization of this
class of AD weapons. According to experts, the modernization potentialities of such
systems as the Shilka and Tunguska have not yet been exhausted and optimal updating can
considerably extend their service life, while their combat effectiveness canl satisfy the
present-day requirements.

The principal
lines of modernization of these systems are described below.

ZSU-23-4
Shilka Self-Propelled Air Defense Gun Mount

The
modernization seeks for state-of-the-art design and technologies to update the
self-propelled (SP) air defense gun mounts and make them effective in heavy electronic
countermeasures (ECM) environments, in adverse weather and dust-laden conditions, in any
season and at any time of day or night. The modernization envisages:

1. Integration
of the modernized Shilka gun mounts into a unified army information system of air target
reconnaissance and designation by organically assigning a mobile air target reconnaissance
and control post (MRCP), Sborka, to the battery as its command post (BCP).

2. Improvement
of the gun mounts main partthe RPK-2 radar-computer complex (85 percent of the
equipment accommodated in the turret) and creation of a new complex, the RPK-2U.

Battery command post:
Sborka MRCP

The radar has
been virtually replaced by a new one, operating on the same frequency band but based on
solid-state components: all units and systems of the radar have been subjected to
modernization and the radar equipment is accommodated in five cabinets (instead of seven).
The RPK-2U complex incorporates:

 digital
computer system (DCS) which jointly with the radar makes up a fire control radar system
(base system);


television-aided sight and laser rangefinder which together with the radar and digital
computer system form an optical-radar fire control system (ORFCS) operating in the passive
mode both day and night (moonlight at a quarter of the moon);


equipment, including:

(a) data
receiving/transmitting (DRT) equipment for the gun mount to exchange information with the
Sborka battery command post via a telecoded communication channel for reception of
external target designation signals and operational control of the Shilka battery engaging
a target by one, two, three and more gun mounts;

(b)
digital-to-analog and analog-to-digital converters;

Ranzhir

(c) trainer for
radar operators;

(d) built-in
equipment for check and adjustment of the RPK-2U complex low-frequency automatics and
turret laying drives (2E2) in static and dynamic conditions;

(e)
commanders guidance unit (CGU).

3. Replacement
of a number of systems, units and assemblies by up-to-date ones boasting higher technical
and operating characteristics.

4. Updating of
the base tracked vehicle and crew life support system.

The fire control
radar system has been modified with the aim to:

 extend
the air situation information field by integrating the gun mount into the unified field AD
system;

 reduce
the time of information processing in the fire control system (dead time);


redistribute regular and random errors and pass bands of the follow-up systems and groups
of the radar- computer complex systems;

 change
the principle of introducing corrections for the angles of tilt and turn of the mount on
the move;

 change
the principle of error determination in the generation of total laying angles of the
automatic guns;

 introduce
and automatically account for meteorological data, corrections for changes in the muzzle
velocity due to barrel bore wear, corrections in orientation and others (all refer to
know-how);

 improve
the radar immunity to passive jamming (with the introduction of angular automation channel
protection and modernization of the MTI system range channel), active range deception
jamming and tracking a jammer by angular coordinates (with the introduction of modes of
tracking by the stored rate of target range variation and its inertial range and
angle-aided tracking by signals from the digital computer system);

 provide
the security of operation in heavy ECM environments (with the introduction of the
optical-radar system);

 improve
the precision characteristics of the follow-up systems and groups of the radar-computer
complex systems;

 reduce
the surveillance time of the fire control system.

The
implementation of the above modifications has enhanced the effectiveness of fighting
high-speed (up to 500 m/s) and small targets maneuvering at altitudes down to 25 m (0 m
with the introduction of the ORS) rather than 100 m.

The air target
(aircraft, helicopter) kill probability during one pass of the engagement zone at an
ammunition expenditure of up to 300 rounds per gun mount constitutes 0.3 to 0.74 (rather
than 0.07 to 0.12) and depends on the organization of control over the combat activity of
the battery gun mounts from the higher command post and engagement of the target by one,
two, three and more mounts. In addition to better technical characteristics, the operating
characteristics have been also improved by providing:

 prompt
functional check of the radar-computer complex and its components;

 means to
upgrade training and practice of radar operators in handling air targets in heavy ECM
environments without aircraft flights (up to five targets with simulation of operation
under conditions of passive and noise jamming);

 better
controllability and maneuverability of the tracked vehicle and reduced labor content
required to maintain and operate the vehicle;

 higher
reliability of starting the traction engine;

 better
habitability conditions.

The service life
of a modernized gun mount after the overhaul of non-modernized systems, units and
assemblies has been extended, with spare parts being supplied.

The
modernization of the Shilka SP gun mount changes the latter into a modern AD system which
fits readily into training, repair and operating structures of clients and can provide
cover of stationary installations, tank and motorized columns on the march in adverse
weather and dust-laden conditions, in any season and at any time of day or night where
other systems outfitted with optical guidance and control systems prove ineffective.


engagement of small targets (cruise missiles of the ALCM type) owing to the use of a radar
proximity target sensor (PTS) with circular radiation pattern;

 increase
of the engagement zone within a range of 8 to 10 km.

Overall, the
combat effectiveness of the Tunguska-M1 system in ECM environments is 1.3 to 1.5 times
higher than that of the Tunguska-M system.

As compared to
the 9M311 air defense missile, the 9M311-1M is noted for:


installation of a radar proximity target sensor in place of the 8-beam laser one;


installation of a pulsed light on the sustainer in place of the flare;

 increased
operating time of the missile components which has allowed the firing range to be extended
from 8 to 10 km.

The Tunguska-M
system can be modernized by the manufacturing plant up to the Tunguska-M1 level.

The
modernization package for the series-produced Tunguska-M system includes:

1. Introduction
of reception and automatically controlled external target designation equipment in the SP
mount. The equipment is interfaced with the battery command post over a radio channel
which allows automatic distribution of targets among the battery SP mounts from the
Ranzhir battery command post and considerably enhances the system combat effectiveness to
repel mass attacks.

2. Introduction
of a relief circuit to significantly facilitate the gunners work in optical tracking
of a moving air target as if it were a stationary one. This considerably reduces tracking
errors, which is essential for engagement of a target by a missile as in this case the
miss value should not exceed 5 m.

3. Improvement
of the coordinate determination equipment due to the application of a new type missile
outfitted with a pulsed light in addition to the source of continuous light. This
innovation significantly enhances the immunity of the equipment to optical decoys and the
kill probability of targets using optical decoys. The employment of the new missile
extends the target engagement range up to 10,000 m.

4. Modified
system for measurement of tilt, gradient and course angles to allow an appreciable
reduction in the perturbing action on gyros which occurs during movement of the SP mount,
reduce errors in measurement of tilt and course angles of the SP mount, enhance the
automatic gun fire control loop stability and, consequently, the kill probability.

The Ulyanovsk
Mechanical Plant, the leading producer of renowned and advanced close-in and medium-range
air defense weapons, offers modernized versions of the Shilka and Tunguska-M systems.

These are our
offers for your consideration. Should you accept them, you will acquire highly effective
air defense systems to ensure your countrys national security.